<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
         div p{
             color: red;
         }
         #father{
             color:red;
         }
         p.c2{
             color: blue;
         }
    </style>
</head>

<body>
     <div id="father" class="c1">
        <p class="c2">
            试问这行文字是什么颜色的？
        </p>
     </div>
</body>

</html>